Be outstanding; shine (5)
I believe the answer is:
excel
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">be outstanding</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >'<span class="explanation-format__original">shine</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ ></span>
(Other definitions for excel that I've seen before include "Be exceptionally good (at a subject)" , "Eclipse" , "Be superior to" , "Be the best" , "Predominate in" .)